During laparoscopic procedures, cannulas are utilized to provide an access port for surgical instruments and a conduit for introducing insufflation gases into the body cavity. In embodiments, a sharp trocar may be positioned within the cannula and utilized to puncture or pierce the tissue or abdominal wall. Thereafter the trocar may be removed, leaving the cannula in place and insufflation gases forced into the body cavity to form an anatomical operating space. Retention of access ports such as cannulas during a laparoscopic procedure is very important, as the ports can be accidentally ejected from the patient, resulting in inconvenience to the surgeon, loss of pneumoperitoneum, and increased procedure time.
In order to prevent an access port such as a cannula from migrating in or out through the incision, some access ports may be provided with anchoring structures to prevent the port from slipping out of the incision. For example, balloons have been used in some devices to assist in anchoring a cannula, as disclosed in U.S. Pat. No. 5,468,248 and U.S. Patent Application Publication No. 2004/0138702, the entire disclosures of each of which are incorporated by reference herein. However, unless the anchoring structure is firmly secured against the tissue, leakage of insufflation gases may occur. Thus, means for anchoring access ports to secure the access port to the tissue and prevent leakage of insufflation gases remain desirable.